A facile one-step solvothermal synthesis of graphene/rod-shaped TiO2 nanocomposite and its improved photocatalytic activity

Abstract

Graphene sheets were obtained through solvothermal reduction of colloidal dispersion of graphene oxide in benzyl alcohol. The graphene/rod-shaped TiO(2) nanocomposite was synthesized by this novel and facile solvothermal method. During the solvothermal reaction, both the reduction of graphene oxide and the growth of rod-shaped TiO(2) nanocrystals as well as its deposition on graphene occur simultaneously. The photocatalytic activity of graphene/rod-shaped TiO(2) and graphene/spherical TiO(2) nanocomposites was compared. In the photocatalytic degradation of methyl orange (MO), the graphene/rod-shaped TiO(2) nanocomposite with the optimized graphene content of 0.48 wt% shows good stability and exhibits a significant enhancement of photocatalytic activity compared to the bare commercial TiO(2) (P25) and graphene/spherical TiO(2) nanocomposite with the same graphene content. Photocurrent experiments were performed, which demonstrate that the photocurrent of the graphene/rod-shaped TiO(2) nanocomposite electrode is about 1.2 times as high as that of the graphene/spherical TiO(2) nanocomposite electrode. The photocatalytic mechanism of graphene/rod-shaped TiO(2) nanocomposite was also discussed on the basis of the experimental results. This work is anticipated to open a possibility in the integration of graphene and TiO(2) with various morphologies for obtaining high-performance photocatalysts in addressing environmental protection issues.

Tuning TiO2nanoparticle morphology in graphene–TiO2hybrids by graphene surface modification

“…Other work on the one-pot synthesis of GNP-TiO 2 hybrids does not show evidence of TiO 2 shape control, [39][40][41][42][43][44] and, when achieved, GNP does not play any significant role in shape control. [45][46][47] In this work, we bind both amino and carboxylate functions on GNP, and we show that these groups can change the morphology of …”

Mechanisms of Reactions Induced by Photocatalysis of Titanium Dioxide Nanoparticles

“…Transient photovoltage spectrum of anatase TiO 2 /graphene demonstrates that the lifetime of the electron-hole pairs is longer compared to bare TiO 2 resulting from the transfer of TiO 2 electrons to the grapheme [401]. Enhanced photocatalytic activity of TiO 2 /graphene hybrids has been observed, although no quantum yields or reaction rates under the same absorbed light density have been reported [402][403][404]. TiO 2 /reduced-graphene-oxide nanocomposites have recently shown nearly 90% enhancement of the UV photocurrent and complete degradation of 2,4-dichlorophenoxyacetic acid [400].…”

Ionic liquid-assisted hydrothermal synthesis of Bi2WO6–reduced graphene oxide composites with enhanced photocatalytic activity

“…† GO shows representative absorptions at 3400 cm À1 (O-H stretching vibration), 1740 cm À1 (C]O stretching vibration of COOH groups), 1631 cm À1 (aromatic C]C vibration), 1406 cm À1 (tertiary C-OH stretching vibration), 1056 cm À1 (C-O stretching vibration), which are in good agreement with previous report. 24 Moreover, no peaks corresponding to [BMIM] [BF 4 ] are discovered in the FT-IR spectra, revealing the easy removal properties of [BMIM] [BF 4 ]. 22,23 In comparison, the absorption peak of C]O (1740 cm À1 ) decreases in intensity or almost disappears in the FT-IR spectra of 5.0%-GRO-BWO composites, suggesting that the oxygen-containing functional groups in GO is removed during the process of hydrothermal reduction and thus GO is reduced to RGO in the composites.…”